Hello, i tried to research this on google but couldnt find much help, was hoping the experts here can explain this to me. StockA price: $42 Nov 50 Call: $0.3 If i naked sell 100 contracts to pocket a premium of ( 0.3 * 100 * 100 ) $3000. I understand that on Nov expiration date if StockA is below or equal to $50, i keep all $3000 and call expires worthless. If StockA is above $50, the call option will get exercised and I will have to buy the stock at market price to cover the $50 call. Now the confusion i have is with the margin requirements associated, how exactly will the margin work in this case? i have a normal brokerage account. 1) What is the margin requirement? is it just the amount of cash i need to have in my brokerage account to cover the short position i have? 1) At the time i sold the 100 contract of naked call for $0.3 premium. What is my margin requirement? 2) What if the underlying StockA goes from $42 to $49, will my margin requirement go up? 3) What if i dont have the required cash in my account to cover the margin requirement in the above example 2) ? Sorry i know those seem basic questions, but i really couldnt find a straight answer from anywhere. Thank you for your help!